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//: arrays/ArrayOptions.java 
// Initialization & re-assignment of arrays. 
import java.util.*; 
import static net.mindview.util.Print.*; 
 
public class ArrayOptions { 
  public static void main(String[] args) { 
    // Arrays of objects: 
    BerylliumSphere[] a; // Local uninitialized variable 
    BerylliumSphere[] b = new BerylliumSphere[5]; 
    // The references inside the array are 
    // automatically initialized to null: 
    print("b: " + Arrays.toString(b)); 
    BerylliumSphere[] c = new BerylliumSphere[4]; 
    for(int i = 0; i < c.length; i++) 
      if(c[i] == null) // Can test for null reference 
        c[i] = new BerylliumSphere(); 
    // Aggregate initialization: 
    BerylliumSphere[] d = { new BerylliumSphere(), 
      new BerylliumSphere(), new BerylliumSphere() 
    }; 
    // Dynamic aggregate initialization: 
    a = new BerylliumSphere[]{ 
      new BerylliumSphere(), new BerylliumSphere(), 
    }; 
    // (Trailing comma is optional in both cases) 
    print("a.length = " + a.length); 
    print("b.length = " + b.length); 
    print("c.length = " + c.length); 
    print("d.length = " + d.length); 
    a = d; 
    print("a.length = " + a.length); 
 
    // Arrays of primitives: 
    int[] e; // Null reference 
    int[] f = new int[5]; 
    // The primitives inside the array are 
    // automatically initialized to zero: 
    print("f: " + Arrays.toString(f)); 
    int[] g = new int[4]; 
    for(int i = 0; i < g.length; i++) 
      g[i] = i*i; 
    int[] h = { 11, 47, 93 }; 
    // Compile error: variable e not initialized: 
    //!print("e.length = " + e.length); 
    print("f.length = " + f.length); 
    print("g.length = " + g.length); 
    print("h.length = " + h.length); 
    e = h; 
    print("e.length = " + e.length); 
    e = new int[]{ 1, 2 }; 
    print("e.length = " + e.length); 
  } 
} /* Output: 
b: [null, null, null, null, null] 
a.length = 2 
b.length = 5 
c.length = 4 
d.length = 3 
a.length = 3 
f: [0, 0, 0, 0, 0] 
f.length = 5 
g.length = 4 
h.length = 3 
e.length = 3 
e.length = 2 
*///:~